delete large file in repository on bitbucket

I accidently have a large zip file on my webserver and it go into the git and now I am at 3.4GB git size. Since my quota is 2GB I am not allowed to do any new pushs or anything. Deleting the zip file from all branches and versions should resolve this, but I am not able to. Since this is urgent, I dont want to wait for support. I need somebody who really knows what to do here.